The invention relates to monomer and polymer adhesive and sealant compositions, and to their production and use for industrial and medical applications.
Monomer and polymer adhesives are used in both industrial (including household) and medical applications. Included among these adhesives are the 1,1-disubstituted ethylene monomers and polymers, such as the .alpha.-cyanoacrylates. Since the discovery of the adhesive properties of such monomers and polymers, they have found wide use due to the speed with which they cure, the strength of the resulting bond formed, and their relative ease of use. These characteristics have made the .alpha.-cyanoacrylate adhesives the primary choice for numerous applications such as bonding plastics, rubbers, glass, metals, wood, and, more recently, biological tissues.
It is known that monomeric forms of .alpha.-cyanoacrylates are extremely reactive, polymerizing rapidly in the presence of even minute amounts of an initiator, including moisture present in the air or on moist surfaces such as animal (including human) tissue. Monomers of .alpha.-cyanoacrylates are anionically polymerizable or free radical polymerizable, or polymerizable by zwitterions or ion pairs to form polymers. Once polymerization has been initiated, the cure rate can be very rapid.
Medical applications of 1,1-disubstituted ethylene adhesive compositions include use as an alternate or an adjunct to surgical sutures and/or staples in wound closure, as well as for covering and protecting surface wounds such as lacerations, abrasions, burns, stomatitis, sores, minor cuts and scrapes, and other wounds. When an adhesive is applied to surfaces to be joined, it is usually applied in its monomeric form, and the resultant polymerization gives rise to the desired adhesive bond.
A concern in the use of adhesive compositions for treating wounds is the flexibility and elasticity of the cured adhesive, particularly in the face and body joint areas, such as hands, feet, elbows and knees.
Polymerized cyanoacrylate compositions are in general not flexible. Increased flexibility would improve the utility of cyanoacrylate compositions, particularly in body joint areas. Improved flexibility and elasticity would also make cyanoacrylate compositions better suited to use as drug delivery devices and the like under some circumstances.
Thus, a need exists for improved adhesive compositions, especially for medical uses, wherein the flexibility and elasticity of the adhesive is improved and the performance of the adhesive composition is not compromised. In particular, the need exists for a monomeric adhesive composition that possesses improved flexibility.
Polydimethylsiloxane (or PDMS) is a silicone compound that was developed for use as a dielectric coolant and in solar energy installations. However, it has also been used in other applications.
U.S. Pat. Nos. 4,477,607, 4,533,422 and Re. 32,889, all to Litke, disclose cyanoacrylate compositions that employ fumed silicas treated with polydimethylsiloxane or trialkoxyalkylsilane to improve the thixotropic properties of the compositions. Likewise, U.S. Pat. Nos. 4,764,545 and 4,686,247 to Yosida disclose an adhesive composition comprising an alpha cyanoacrylate and a silica surface-treated respectively with polydimethylsiloxane and with hexamethyldisilazane. Similarly, JP 06-122853 discloses an adhesive composition comprising an alpha cyanoacrylate and a hydrophobic silica surface-treated with dimethyldichlorosilane; U.S. Pat. No. 4,636,539 to Harris et al. discloses an adhesive comprising cyanoacrylate adhesive, fumed silica filler treated with polydialkylsiloxane, and calixarene compound; U.S. Pat. No. 4,180,911 to Bullock discloses a composition and method for use of a cyanoacrylate resin and a silane-treated inorganic powder in direct bonding of an orthodontic bracket structure to teeth and other dental applications; U.S. Pat. No. 4,713,405 to Koga et al. discloses an adhesive composition comprising an alpha cyanoacrylate and a fumed silica having a surface treated with a dimethyldichlorosilane and trialkyl borate; U.S. Pat. No. 5,373,035 to Uemura et al. discloses an adhesive composition comprising an alpha cyanoacrylate and a hydrophobic silica surface-treated with dimethyldichlorosilane; and U.S. Pat. No. 5,248,708 to Uemura et al. discloses an adhesive composition having a particular alpha cyanoacrylate, a fine silica and silanol group.
U.S. Pat. No. 5,214,093 to Nell et al. discloses an adhesive mixture for nonsurgical blepharoplasty. In the main embodiments, the base adhesive component is an oxygen permeable polysiloxane in a solvent. A less preferred embodiment includes a homogeneous mixture of cyanoacrylate adhesive and two separate miscible silicon oil components that are said to provide lubrication and breathability to the skin surface. These components are disclosed to be used in amounts of 50% cyanoacrylatc, 25% polydimethylsiloxane and 25% 3-methacryloxy propyltris (trimethoxysiloxy) silane, and can be applied serially or in a mixture. The patent states that the mixture adheres in approximately five minutes and remains somewhat flexible during that time. It provides no further detail about the PDMS other than to indicate that it is "very oily and will penetrate the surface of the tissue to some extent." It is noted that silanes as a general matter raise toxicity issues, although this is not discussed in the Nell patent.
JP 57-70169, JP 57-70171, JP 03-126782, JP 03-296581, JP 04-146982 and JP 06-100838 disclose .alpha.-cyanoacrylate adhesive compositions containing specific organosilicon compounds including silicone oils and compounds related to PDMS. However, the disclosed compounds include various side and/or terminal groups that raise issues as to the stability and utility of the resultant compositions.
U.S. Pat. No. 4,906,317 to Liu discloses a cyanoacrylate adhesive composition which employs silacrown compounds as additives.
U.S. Pat. No. 4,837,260 to Sato et al. discloses an adhesive composition comprising an alpha cyanoacrylate and a hydrophobic silica along with particular curing accelerators.
U.S. Pat. No. 4,650,826 to Waniczek et al. discloses the use of silyl ester as a stabilizer for a cyanoacrylate adhesive.
U.S. Pat. No. 5,386,047 to Nakos et al. discloses a polymerizable composition comprising a monomer component, which includes a silicon containing di-alpha-cyanopentadienoate disiloxane compound. The monomer component further includes an alpha cyanoacrylate compound.
U.S. Pat. No. 4,705,836 to Ohtsuka et al. discloses a bonding composition including vinyl benzoic acid and cyanoacrylic acid ester. The composition further contains a silane compound.
U.S. Pat. No. 5,140,084 to Mikuni et al. discloses a silicone-containing alpha-cyanoacrylate that is useful as an adhesive. Similar silicone-containing alpha-cyanoacrylate compositions are also disclosed in JP 04-9388 and JP 04-8780.